Process of, and a plant for, constructing tunnels

ABSTRACT

A plant for use in tunnel constructions and having a drive shield with a cutting head for driving into a working face to advance the tunnel. A plurality of rams which act upon an abutment member are used to drive the shield forwards. The abutment member transmits the forces from the rams to a mass of fluid concrete introduced under pressure and supported on support means such as a tubular shell or series of rings spaced inwardly from the tunnel wall. The concrete when hardened forms a continuous lining for the tunnel wall. Water is removed from the fluid concrete with the aid of filters provided on the abutment member of the support means.

United States Patent [191 Lobbe et a1.

[ June 17, 1975 1 PROCESS OF, AND A PLANT FOR,

CONSTRUCTING TUNNELS [73] Assignee: Gewerkschaft Eisenhutte Westialia,

Westphalia, Germany [22] Filed: May 1, 1974 [21] Appl. No.: 465,942

Related U.S. Application Data [62] Division of Ser. No. 292,470, Sept. 26, 1972, Pat.

[30] Foreign Application Priority Data Sept. 26, 1971 Spain 395457 Nov. 12, 1971 Spain 396949 [52] U.S. Cl 61/85; 61/72.2 {51] Int. Cl. E01g 5/08 [58] Field of Search 61/85, 84, 45, 72.2;

[56] References Cited UNITED STATES PATENTS 2,149,029 2/1939 Michelson et a1. 425/84 2,730,783 1/1956 Kennison 425/84 3,396,545 8/1968 Lamberton 61/45 X 3,550,382 12/1970 Khodosh et a1 61/84 FOREIGN PATENTS OR APPLICATIONS 443,158 2/1935 United Kingdom 61/85 Primary Examiner-Jacob Shapiro Attorney, Agent, or FirmSughrue, Rothwell, Mion, Zinn & Macpeak ABSTRACT A plant for use in tunnel constructions and having a drive shield with a cutting head for driving into a working face to advance the tunnel. A plurality of rams which act upon an abutment member are used to drive the shield forwards. The abutment member transmits the forces from the rams to a mass of fluid concrete introduced under pressure and supported on support means such as a tubular shell or series of rings spaced inwardly from the tunnel wall. The concrete when hardened forms a continuous lining for the tunnel wall. Water is removed from the fluid concrete with the aid of filters provided on the abutment member of the support means.

4 Claims, 4 Drawing Figures PATENTEDJUN 17 I975 SHEET IIIIL ff/l/ I flrfvfl r 1 PROCESS OF, AND A PLANT FOR, CONSTRUCTING TUNNELS This is a division of application Ser. No. 292,470 filed Sept. 26, 1972, now US. Pat. No. 3,834,170.

BACKGROUND OF THE INVENTION The present invention relates to a process of, and plants for, constructing a tunnel.

In tunnel construction it is known to support the wall of the tunnel behind the excavating or driving work with a concrete lining. It is desirable to introduce fluid concrete to form such a lining as near as possible to the working face and to introduce the fluid concrete as soon as possible after a fresh advance. Hitherto the time required for the concrete to harden has slowed down the rate at which the tunnel can be advanced.

A general object of the present invention is to provide an improved process of and plants for constructing tunnels.

SUMMARY OF THE INVENTION In a process of constructing a tunnel by advancing a drive shield into a working face and by forming a concrete lining for supporting the tunnel wall produced by the drive shield; the invention comprises, in one aspect, removing water from the fluid concrete used to form the lining via at least one filter. In this Way the concrete can be hardened more rapidly and preferably the fluid concrete is introduced under pressure to ensure an adequate quantity of water is removed.

However, the invention also comprises supporting a mass of fluid concrete used to form the lining and using said mass of concrete as an abutment for driving the shield forward before said concrete has hardened. More particularly, the rams used for advancing the shield may act against the concrete. In this way the advance of the tunnel can be virtually continuous since there is no necessity to wait for the concrete to harden before advancing the shield. The advance of the shield serves to compress the concrete to expell more water therefrom and this results in a concrete lining of good quality and density being produced.

The invention also provides a plant for constructing tunnels which plant includes means for supporting fluid concrete used to form a lining for the tunnel, and one or more filters allowing water to be removed from said fluid concrete.

The plant thus enables the tunnel to be constructed more quickly and economically than hitherto. In general the driving operation and the introduction of fresh fluid concrete can take place in succession to one another.

Preferably an abutment member is disposed between the rams used to advance the drive shield and the concrete. The support means can take the form of a tubular shell spaced inwardly from the tunnel wall and attached to the abutment member. Alternatively the support means can be slidable in relation to the abutment member or merely engageable therewith. The support means can also in these latter alternatives, be in the form ofa series of rings. The shell or rings may have the filters therein but it is also possible for the abutment member to be provided with these components. The abutment member may also define or partly define a chamber for initially receiving the concrete.

In the case where the abutment member has the filters this causes the concrete to harden more quickly in a zone which is adjacent the filters. Although this does have some advantage in preventing flowing of the concrete and transmitting the thrust forces of the rams the presence of the zones of pre-hardened concrete is disadvantageous in the lining and hence it is desirable to use a vibrating device or similar to destroy these zones and disperse the agglomerations of hardened concrete into the ore fluid concrete.

The invention may be understood more readily and various other features of the invention may become more apparent from consideration of the following description.

BRIEF DESCRIPTION OF DRAWINGS Embodiments of the invention will now be described by way of example only, with reference to, and as illustrated in, the accompanying drawings, wherein FIG. 1 is a schematic longitudinal sectional view of a tunnelling plant made in accordance with the invention;

FIG. 2 is a schematic longitudinal sectional view of a further tunnelling plant made in accordance with the invention;

FIG. 3 is a schematic longitudinal sectional view of another tunnelling plant made in accordance with the invention; and

FIG. 4 is an end view of part of the abutment member used in the plant depicted in FIG. 3.

DESCRIPTION OF PREFERRED EMBODIMENT Referring initially to FIG. 1, the plant has a drive shield 10 formed at its forward end with a cutting head 12. A plurality of hydraulic rams 11 are used to drive the shield 10 in the direction of arrow V to cause the head 12 to penetrate a working face. Material is removed from the face and conveyed rearwardly through the shield 10 and the tunnel previously constructed. This is well known per se. As the tunnel progresses the wall of the tunnel is supported by a concrete lining 13 formed in situ. To this end, a tubular shell 14 having an abutment member 15 at its forward end is provided. The member 15 engages the rams 11 and absorbs the thrust forces when the shield 10 is driven forwards. The member 15 is a double-walled structure, having a rearwardly projecting extension 16 which, with the main body of the shell 14, defines a chamber for receiving fluid concrete from pipes 17 for forming the lining 13. The portion of the concrete lining denoted 18 is supported by the shell 14 during its setting process. The shell 14 is provided with one or more filters 19 which enable water to pass from the fluid concrete into the interior of the shell 14.

During operation the shield 10 is advanced and the shell 14 is then drawn up towards the shield 10. Fluid concrete is pumped under pressure, preferably in the order of 25 atmospheres, into the chamber between the extension 16 and the main body of the shell 14 via the pipes 17. This fluid concrete tends to move rearwardly, over the portion 18 supported by the shell 14. Since the fluid concrete is under pressure water is urged through the or each of the filters 19. The fluid concrete is supported radially between the shell 14 and the tunnel wall and axially by the existing hardened lining 13 and the member 15. Hence although the introduced concrete has not set it can still form a rear support for the abutment member 15 when the rams 11 next drive the shield 10 forwards. The concrete is in fact compressed by the operation of the rams 1 1 so that water is again forced out of the concrete and through the or each of the filters 19. The cycle is then repeated and the overall tunnel driving process can thus take place continuously without waiting for the newlyintroduced concrete to harden.

The plants depicted in FIGS. 2-4 are similar to that shown in FIG. 1 and like reference numerals are used to denote like components. As shown in FIG. 2 the FIG. 1 arrangement is modified so that a series of rings 21 provided with filters 22 replaces the shell 14 as a support to the fluid concrete mass. A double-walled abutment member 20 defines a chamber for receiving fluid concrete and again takes the thrust forces from the rams 11. The inner wall of the member 20 slidably engages the exterior periphery of the rings 21. By adding more rings 21 the radial support for the concrete can be lengthened. The plant is operated in the same manner as described above with the member 20 sliding over the rings 21 as the rams ll draw up the member 20 prior to the introduction of the fluid concrete.

In the plant shown in FIGS. 3 and 4 the rams 11 are again supported rearwardly by an abutment member, here denoted 30. As shown in FIG. 4 the member 30 is of double-walled hollow structure with an annular configuration. Filters 31 are provided on the rear annular surface of the member 30. A series of rings 32 are connected together to form a support for the fluid concrete. In a similar manner to the other embodiments, fluid concrete is pumped into the space 33 between the tunnel wall and the periphery of the rings 32. Water from this concrete passes through the filters 31 and as a result the concrete located in a zone a adjacent the member 30 tends to harden more rapidly than the remaining concrete. When the shield is driven forward by the rams 11 the concrete is compressed by the abutment member 30 to augment this zonal hardening of the concrete. After advance of the shield 10 a further ring 32 would be installed and the concrete again fed in as before. The zonal hardened concrete a prevents the more fluid concrete from flowing forwardly and possibly running between the member 30 and the foremost ring 32 when the formers is drawn up by the rams 11 and the fresh ring 32 is installed. However as a result of the zonal hardening, sections or rings of hardened concrete in the mass of generally still fluid concrete form at the junctures between the rings 32, i.e. at the zones denoted a, b and c in FIG. 3, it is desirable to destroy these isolated sections of hardened concrete after they have served their useful function to cause the hardened concrete to be dispersed in the still fluid concrete. In this way discontinuities which could cause cracking and fracture of the lining can be prevented. T0 destroy the hardened concrete sections it is preferable to use some form of vibrating device to break up or crush the sections. Such a device may act at the juncture between two adjacent rings 33 to-vibrate the matter as indicated diagrammatically by numeral 34 in FIG. 3.

We claim:

1. In a process of constructing an underground tunnel including the steps of operating a plurality of rams to advance a movable drive shield into a working face, introducing fluid concrete into a confining chamber rearwardly of the shield relative to the working face to form a lining for supporting the tunnel wall, and utilizing said fluid concrete as an abutment for the rams during the advancement of the drive shield, the improvement comprising: removing water from the fluid concrete used to form the lining through filter means, whereby the water passes out from the chamber to thereby accelerate the setting of the concrete.

2. A process according to claim 1, wherein the water is driven out fro'm the fluid concrete in the chamber by ,a pressure differential established across the filter means.

3. A process according to claim 1, wherein the fluid concrete is introduced under pressure.

4. A process according to claim 1, wherein the fluid concrete is introduced in alternation with the advancement of the shield. 

1. In a process of constructing an underground tunnel including the steps of operating a plurality of rams to advance a movable drive shield into a working face, introducing fluid concrete into a confining chamber rearwardly of the shield relative to the working face to form a lining for supporting the tunnel wall, and utilizing said fluid concrete as an abutment for the rams during the advancement of the drive shield, the improvement comprising: removing water from the fluid concrete used to form the lining through filter means, whereby the water passes out from the chamber to thereby accelerate the setting of the concrete.
 2. A process according to claim 1, wherein the water is driven out from the fluid concrete in the chamber by a pressure differential established across the filter means.
 3. A process according to claim 1, wherein the fluid concrete is introduced under pressure.
 4. A process according to claim 1, wherein the fluid concrete Is introduced in alternation with the advancement of the shield. 